This proposal requests funding for a joint symposium to include neuroendocrinologists from the United States and from Japan. The Symposium is entitled: "US/Japan Symposium on Neuroplasticity, Development and Steroid Hormone Action". The symposium will be held September 26-29, 2000 at the East-West Center in Honolulu, HI. The primary goal of this symposium s to bring together neurobiologists from the United States and Japan to interact and discuss their current research related to the study of steroid hormones and their action in the brain. This is often difficult given the financial and geographical constraints of travel between the United States and Japan, and thus, a site situated between both countries has been chosen. A second goal of this symposium is to foster in- depth exchange of new ideas and to encourage collaborative and cross- disciplinary interactions. This will be achieved by intentionally limiting the size of the symposium and not associating it with a meeting of a national organization. The Organizing committee has selected session topics and speakers within each session that address the most important areas in steroid hormone action in the brain and that span the lifetime of the animal, from fetal development to age-related changes. The makeup of each session has been deliberately designed to be interdisciplinary in order to foster discussion. Within each session, scientists from early, middle and late stages of their careers have been chosen to present their research. Investigators using a range of model systems and technical approaches have been included. The final goal of this symposium is to establish a conduit for future scientific exchange between the United States and Japan that will ultimately benefit the neuroendocrine communities of both countries.